High Temperature Waste Pasteurizer

Brian KilgerKyle Cohn

Kyle WestonStephanie Mauro

Parabolic curve

P13411

The Team

Kyle Weston- Team Leader

Stephanie Mauro- Thermal Engineer

Kyle Cohn- Alternative Energy Engineer

Brian Kilger- Materials Engineer

Agenda

• Feedback (expectations and priorities for review)• Problem Definition• Customer Needs and Specs• Concept Development• Concept Selection• Feasibility• Risks and Risk Assessment• Schedule

Feedback We are Looking for from This Review

• Alternative design concepts

• Feasibility of materials

• Compatibility of our ideas with Haiti

Problem Statement

• The primary objective of this project is to transform human waste into a safe to use fertilizer using renewable energy. The waste pasteurizer must be made of materials available in Haiti and be easy to use.

Customer Needs/Design SpecificationsEngineering Specification

Derived from Customer Need

Relative Importance Description Measure of

Performance Engineering Units Marginal Value Ideal Value

ES1 CN2, CN11 9 Provide heat to waste using solar energy in order to kill pathogens

Temperature, Time °F, hours 122°F, 1 week

ES2 CN4 9 Vent combustive gases in order to prevent explosions and smell

Amount of methane inside chamber

ppm 50,000 Less than 30,000

ES3 CN1, CN4 9 Contain pathogens, do not allow unsafe leakage of untreated wastes

Is there leakage? Binary (Yes/No) No No

ES4 CN4 9 Temperature of the access door (or handle of the access door) Temperature °F 120°F Less than 100

°F

ES5 CN1, CN5 9 The product must be able to withstand an outdoor environment IEC60529* digit

2 Level 0-8Binary (Yes/No)

ES6 CN1, CN5 3 The product must be able to withstand an outdoor environment

Does the product withstand outdoor wind

mph 20 mph 25 mph

ES7 CN4, CN7, CN8 3Customer must be able to easily add, stir (optional) and remove waste

Time to add, stir and remove material

minutes 15 minutes less than 5 minutes

ES8 CN12, CN7, CN9, CN11 3 Volume of product accommodated Volume Liters

1L per person per day* and cover material

ES9 CN2 9Does the entire sample of human waste contain safe pathogen levels?

Test for temperature and E. coli (if using manure)

See attached table. Refer to Humanure Handbook for more details

ES10 CN13 1 Shows disinfection has taken place Yes

Key Specifications • Provide heat to waste• Vent combustive gases• Contain pathogens• Temperature of access

door (Safe handling)• Environmental

durability• Safe• Easy to use• Use local resources

• Destroy all pathogens• Reusable• Easy to maintain

Functional Analysis

Systems Architecture

Concept Development: Morph Chart

System Concepts

1. Pot on stand, heat from top and bottom2. Box on stand with drawer, heat from top and bottom3. Double box on group, heat from top and reflectors 4. Bare minimum option: hole in ground, direct

sunlight only5. Expensive option: box with drawer, solar panels,

insulation6. Complex option: heat exchanger, heated from

reflectors and top

The Datums

• Capetown Project– Tin box w/ tray– Pasteurized human

waste in 6 hours using direct sunlight

• CooKit– Cheap (~$25 USD)– Pot in bag sitting on

mirrors– Not user friendly

Datum 1: Pugh Chart ConceptsSelection Criteria Weight Datum 1 1 2 3 4 5 6Mechanical Simplicity - - - + - -Input Simplicity S S S + S SBiproduct Containment S S S - - SFeces Containment + S + - S SHeating Simplicity - - - S - -Power Output 2 + + + S + +Time of Completion 2 + + + + + +Ability to Maintain Temperature S S S - S SOutput Simplicity S S S - S SBiproduct Removal S - - - - -Excess Buildup Removal S S S S S SHeat Protection + + + - + +Protection from Edges + S S + S SDurability - - - + - -Cost - - - + - -Sum (+)'s 7 5 6 7 5 5Sum (S)'s 6 7 6 3 6 7Sum (-)'s 4 5 5 6 6 5Net Score 3 0 1 1 -1 0Rank 1 4 2 2 6 4

Datum 2: Pugh Chart ConceptsSelection Criteria Weight Datum 2 1 2 3 4 5 6Mechanical Simplicity - S S + S SInput Simplicity S S S + S SBiproduct Containment + + + - + +Feces Containment S S S - S SHeating Simplicity - S S + S -Power Output 2 + + + - + +Time of Completion 2 + + + - + +Ability to Maintain Temperature S S S - S SOutput Simplicity + + + S + +Biproduct Removal S - S - - -Excess Buildup Removal S S S S S SHeat Protection + + S - + +Protection from Edges S - - + - -Durability - S S + S SCost - - - + - -Sum (+)'s 7 7 6 6 7 7Sum (S)'s 6 7 9 2 7 6Sum (-)'s 4 3 2 9 3 4Net Score 3 4 4 -3 4 3Rank 4 1 1 6 1 4

Average Rank 2.5 2.5 1.5 4 3.5 4NET Rank 2 2 1 6 4 6

Concept SelectionConcept 1

Pugh Chart Rating: 2Concept 2

Pugh Chart Rating: 2Concept 3

Pugh Chart Rating: 1

• Pot raised above ground in a stand – removable.

• Heated from direct sunlight to top and reflected onto bottom.

• Removable lid for input/output.

• Gasses vented.

• Box raised above ground in a stand

• Heated from direct sunlight to top and reflected onto bottom.

• Removable drawer for input/output.

• Pressure relief valve to eliminate gasses.

• Box inside of a box• Heated from direct

sunlight to top and reflected from side flaps.

• Removable lid and inner box.

Feasibility [J]

[W]

Estimated Mass of Waste to be Heated, m 1.134 kgSpecific heat of Water, Cp 4183 J/(kgK)Initial Temperature, Tinitial 25 C

Time for Pastuerizing

[hrs]Final Temp

[C]Delta

Temp [K]Time to reach

Temp [s]Q[J]

q[W]

1 60 35 3600 166023.27 46.12

10 53 28 3600 132818.62 36.89

24 50 25 3600 118588.05 32.94

Feasibility

• Solar irradiance data was collected from Puerto Rico using the average conditions by day for the past 40 years

• Determined how many days the minimum wattage was met for 5 hours

• Calculations show that 303 days will meet our needs

Risks and Risk Assessment

Risks and Risk Assessment

Risks and Risk Assessment

Schedule

Schedule Task List

Any Additional Questions?

Thank You All for Your Time and Feedback